Income Taxes - Income tax provision (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Current
Federal	$ (190)	$ 69
State	1	2
Foreign	194	155
Total current	5	226
Deferred Income Tax Expense (Benefit), Continuing Operations [Abstract]
Federal	(7)	2
State	86	2
Foreign	(7)	56
Total deferred	(100)	56
Total income tax provision (benefit)	$ (95)	$ 282

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